netconf/netconf-mapping-api/src/main/java/org/opendaylight/netconf/mapping/api/HandlingPriority.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.netconf.mapping.api;
   9
  10 import static com.google.common.base.Preconditions.checkArgument;
  11 import static com.google.common.base.Preconditions.checkState;
  12
  13 import com.google.common.base.MoreObjects;
  14 import java.util.Objects;
  15 import java.util.Optional;
  16
  17 public final class HandlingPriority implements Comparable<HandlingPriority> {
  18
  19     public static final HandlingPriority CANNOT_HANDLE = new HandlingPriority();
  20     public static final HandlingPriority HANDLE_WITH_DEFAULT_PRIORITY = new HandlingPriority(Integer.MIN_VALUE);
  21     public static final HandlingPriority HANDLE_WITH_MAX_PRIORITY = new HandlingPriority(Integer.MAX_VALUE);
  22
  23     private Integer priority;
  24
  25     public static HandlingPriority getHandlingPriority(final int priority) {
  26         return new HandlingPriority(priority);
  27     }
  28
  29     private HandlingPriority(final int priority) {
  30         this.priority = priority;
  31     }
  32
  33     private HandlingPriority() {
  34     }
  35
  36     /**
  37      * Get priority number.
  38      *
  39      * @return priority number or Optional.absent otherwise
  40      */
  41     public Optional<Integer> getPriority() {
  42         return Optional.ofNullable(priority);
  43     }
  44
  45     public HandlingPriority increasePriority(final int priorityIncrease) {
  46         checkState(priority != null, "Unable to increase priority for %s", this);
  47         checkArgument(priorityIncrease > 0, "Negative increase");
  48         checkArgument(Long.valueOf(priority) + priorityIncrease < Integer.MAX_VALUE,
  49                 "Resulting priority cannot be higher than %s", Integer.MAX_VALUE);
  50         return getHandlingPriority(priority + priorityIncrease);
  51     }
  52
  53     public boolean isCannotHandle() {
  54         return this.equals(CANNOT_HANDLE);
  55     }
  56
  57     @Override
  58     @SuppressWarnings("checkstyle:parameterName")
  59     public int compareTo(final HandlingPriority o) {
  60         if (this == o) {
  61             return 0;
  62         }
  63         if (isCannotHandle()) {
  64             return -1;
  65         }
  66         if (o.isCannotHandle()) {
  67             return 1;
  68         }
  69
  70         if (priority > o.priority) {
  71             return 1;
  72         }
  73         if (priority.equals(o.priority)) {
  74             return 0;
  75         }
  76         if (priority < o.priority) {
  77             return -1;
  78         }
  79
  80         throw new IllegalStateException("Unexpected state comparing " + this + " with " + priority);
  81     }
  82
  83     @Override
  84     public boolean equals(final Object obj) {
  85         if (this == obj) {
  86             return true;
  87         }
  88         if (!(obj instanceof HandlingPriority)) {
  89             return false;
  90         }
  91
  92         HandlingPriority that = (HandlingPriority) obj;
  93
  94         return Objects.equals(priority, that.priority);
  95     }
  96
  97     @Override
  98     public int hashCode() {
  99         return priority != null ? priority.hashCode() : 0;
 100     }
 101
 102     @Override
 103     public String toString() {
 104         return MoreObjects.toStringHelper(this)
 105                 .add("priority", priority)
 106                 .toString();
 107     }
 108 }